Thursday, January 22, 2015

Just before Christmas a murder trial collapsed when the prosecution failed to lay the correct evidential basis for admitting mobile phone records against the accused. There's no written judgment but according to media reports:

The State entered a nolle prosequi in the case after Judge Catherine Murphy ruled that telephone records held on a mainframe computer could not be relied on as evidence because there was no evidence that the computer was operating correctly at the relevant time...

In her ruling at Dublin Circuit Criminal Court Judge Murphy said there must be evidence of the function and operation of the main frame computer, on which the call records are held. She said: “This must include information that the computer was operating correctly at the relevant time”.

The ruling relies on a 1992 judgement from the UK appeal courts which held that the prosecution must provide evidence of the function and operation of the mainframe computer used to store the records. The Cochrane ruling, which has been upheld by the Irish courts, noted that “the problem of proving transactions of this type must now arise frequently and it should be possible… to devise a standard form of evidence to deal with it.”

Judge Murphy had earlier ruled that the evidence of the records held on the Meteor mainframe server was not admissible under the 1992 Criminal Evidence Act because the act does not cover automatically held records.

The evidence in this case was that the records were held, automatically, on the Meteor mainframe server. The prosecution then submitted to the Court that the records could be admitted under Common Law. Judge Murphy ruled against them on this and noted that the UK judgement states there must be evidence “that the computer was operating correctly at the relevant time”.

The UK judgement states that the prosecution must provide “authoritative evidence about the operation of the relevant machines”. Judge Murphy noted that an engineer from Meteor gave evidence for the prosecution that he had working knowledge of the Meteor computer system but not of the mainframe computer from on the records were held.

The legal argument centred on whether records from mobile phone masts could be relied on to link the phones to the robbery by placing them at relevant times and places. Detectives have developed the network of phones out of a single call allegedly made from the Dublin Mountains to the Richardson family home during the kidnapping. Mrs Richardson testified that the gang had allowed her to call her husband from the mountains. In ruling on the defence application, made in the absence of the jury, Judge Ring said that none of the three mobile phone network experts called by the prosecution could say that the relevant networks were fully operational and functioning on a given day or whether any particular cell sites are out of operation on those relevant dates. She said there was evidence that calls could be routed through another mast if the nearest mast was not operational at the time or if it was busy.

The Cochrane judgment referred to in these reports is R v. Cochrane [1993] Crim LR 98, which was applied in Ireland in relation to mobile phone records by People (DPP) v. Colm Murphy [2005] IECCA 1. It's a little surprising, therefore, that admissibility has become such a contentious issue nearly a decade later. As far as I can tell from the newspaper reports, what has happened is that trial judges have become more familiar with the technology and have become more strict in insisting that the prosecution witnesses can testify to the operation of the system as a whole and not just particular components such as the masts. In the short term this is going to require prosecutors to put forward more technical witnesses from the mobile operators; longer term I wouldn't be surprised to see legislation rushed forward to provide a statutory basis for admitting these records (probably on the basis of certificate evidence).

Incidentally, this is certainly not limited to the case of mobile phone records - the same logic would apply to evidence of IP address allocation and use and other computer evidence. Expect these arguments to be played out soon in other cases involving computers.